Ms Betancourt has described her six years in captivity as agonising
Ingrid Betancourt, a former prisoner of Farc rebels in Colombia, was selfish and domineering in captivity, three fellow hostages say in a new book.
In their memoir, the three US military contractors describe their five-year ordeal in the jungles of Colombia.
One of them says that Ms Betancourt was even worse than the Farc guards.
Ms Betancourt, the French-Colombian ex-politician, received a hero's welcome upon her rescue last year. She has not commented on the Americans' account.
'Out of control'
Keith Stansell, Thomas Howes and Marc Gonsalves were freed alongside Ms Betancourt and 11 Colombians by soldiers posing as aid workers in a daring operation hailed around the world.
In their book they take turns narrating their experience as hostages with Colombia's main leftist rebel group, which has been fighting to overthrow the government since the 1960s.
They describe forced marches, meagre rations and mind-numbing boredom. They also had to compete with other prisoners for sleeping space, food and the sole Spanish-English dictionary.
The harshest words for Ms Betancourt are from Mr Stansell, who accuses her of telling their Farc guards that the Americans are CIA agents, a charge other freed hostages have denied.
"Ingrid had sent notes to [Farc commander] Sombra telling him that we were CIA agents and she wanted us out of there for that reason," Mr Stansell writes.
The 44-year-old former marine said Ms Betancourt tried to dominate the camp.
"I watched her try to take over the camp with an arrogance that was out of control," he told the Associated Press in an interview before the book was published.
"Some of the guards treated us better than she did."
Mr Gonsalves says Ms Betancourt put pressure on Farc commanders to keep the Americans out of her shelter.
"She wasn't making a request, but issuing a command," he writes. "She wanted us put in some other part of the camp."
However, he writes that his opinion of her changed after she agreed to share her radio with him.
"Maybe she was not the person we thought she was. Maybe Ingrid has a far more complicated and multi-dimensional person than she'd allowed us to believe."
Mr Gonsalves developed a close friendship with Ms Betancourt, he says, and came to admire the former Colombian presidential candidate.
"She's a tough woman. She used to give those guerrillas a hard time."
In response to the criticism, Ms Betancourt's spokeswoman told the Associated Press that she was "dedicated to writing her own book and not making declarations until it is finished."
There has also been interest from Hollywood producers in turning her story into a film.
Ms Betancourt has said that her six years of captivity was an agonising ordeal only lessened by snatched radio broadcasts heard on an illicit radio and the support of fellow prisoners.
Since her release, Ms Betancourt has continued to campaign for the release of about two dozen high-level hostages Farc is holding for political gain and hundreds of other being held for cash ransom.